I had posted previously about my calla plant yellowing and shriveling up overnight. We suspected it was going dormant. With all the leaves and stalks detaching, I dug the bulb up and stored it inside a mixture of peat moss and compost. I checked on the bulb today and I noticed all the roots had gone black, and it had a very fleshy spot on the body where the roots came from. All the roots have come off now, and there is also a layer of "skin" that appears to be coming off. What should I do? Is this normal? Sadly I can only upload one picture. Thanks
This is root rot. Your bulb essentially is rotting and should be discarded.
Well draining soil is essential so that the bulb and roots do not sit in water.
Here are a couple of great links.